Incubator



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Aug 14, 1951 F11ed Ju1y 11, 1947 ff/L Patented ug. i4, 1951 UNITED STATES PATENT OFFICE INCUBATOR iLot J. Seacat, Ramsey, Ind.

Application July 11, 1947, Serial No. 760,266

6 Claims.

'I'his invention relates to incubators for hatching poultry eggs. The hatching of eggs is now a vast mass production industry in which many millions of eggs are hatched annually by incubation. In a customary procedure, the eggs to be hatched are transferred from standard crates to hatching trays. These trays are then loaded into an incubator. The frame carrying these trays within the incubator may be tiltable; or mechanism may be provided for tilting the trays periodically in order to effect the movement of the eggs necessary for hatching. However, as is well known, the eggs must remain motionless during the final 3 of the 21-day hatching period. Where continuous hatching is being done, it is necessary, just prior to the final 3 days, to transfer the trays of eggs to another incubator in order that these eggs which have been in the incubator less than 19 days, may be periodically moved. This transfer involves a large amount of time, expense, and added equipment and, furthermore, involves the possibility of loss because of breakage and careless handling of the trays or eggs.

It is accordingly the main and general purpose of my invention to provide an incubator inv which the drawbacks inherent in the prior art incubators, as just described, are eliminated.

More specifically, it is an object of the invention to provide an incubator wherein the eggs and their trays are untouched from the time they are first placed in the machine until the eggs are hatched.

Another object is to provide an incubator adapted, without structural change,- to the simultaneous hatching of a full capacity of eggs, or to the sequential hatching of a predetermined number of eggs at different times.

A further object is the provision of an incubator which can be constructed in sections and to which sections may be added as desired by the owner, when it is desired to expand the capacity of the machine.

A still further object is the provision of an incubator wherein a great saving of labor and costs of operation may be effected over the prior art machines.

Yet another object is to provide an incubator in which axially aligned sections may as desired be simultaneously oscillated to move the eggs or leave them quiescent during the final hatching period.

Other objects and advantages of my invention will become apparent after a study of the following description.

In the drawings:

Figure 1 is an elevation of the front end of the incubator, the front wall being removed to illustrate the mounting of the truck supporting frame and the power drive thereto.

Figure 2 is a sectional detail view showing to an enlarged scale the,L roller mounting of two adjacent incubator sections together with their connecting sleeve, substantially as viewed in a plane indicated by line 2 2, Figure 1.

Figure 3 is an elevation substantially on line 3-'3, Figure 1, showing the details of the motor control and speed reducing drive to the incubator sections,

Figure 4 is a wiring diagram corresponding to Figure 3.

Figure 5 is a Iperspective view of a complete machine using seven incubator sections or units.

Figure 6 is a detail view showing a portion of the end of an egg truck.

Referring in detail to the drawing, l indicates generally a housing which may consist of a plurality of circular tracks such as 2, spaced along and concentric of a common central axis 3, Figure l. In the model illustrated each track comprises a channel bent into form with its flanges inward- 1y. Each track may be supported by a base channel 4 to the ends of which are connected by brace plates 5, uprghts 6 and 1. These uprights may be simple angles and have a length approximately equal to the radius of tracks 2 and secured to the tracks by plates 8. In the model shown, the tracks 2 have a diameter of approximately 81/2 feet and the number required is one more than the number of incubator sections used. Thus, where seven sections are employed, as shown at Figure 5, eight circular tracks and supports will be used.

The circular tracks 2 are secured in aligned preferably equally spaced position by any suitable means such as longitudinal stringers 9, assisted, of course by outer covering or sheathing l0 which may be of plastic, plywood, or sheet metal, corrugated or plain. By this means the housing is united into a rigid unit comprising a selected number of sections each alittle more than two feet and three inches in axial dimension.

rIhus the over-all length or axial dimension of the machine illustrated is about sixteen feet.

Each circular track 2 has the edges of its flanges smoothed and one flange of each track has gear teeth formed therein over of arc, as indicated at ll, Figures 1 Vand 2. Preferably this rack is formed in the upper left quadrant although it may be formed over any other portion of the track and may be greater or less than 90. The dividing lines between sections are indicated 3 at I2, Figure 5, and it will be understood that a plane through each section line I2 will pass midway between the flanges of the corresponding track 2.

Each incubator section includes a rectangular frame generally indicated at I3. The frame is square in the model shown and is about six feet on a side. Each frame is built up of angle sec- Itions, including verticals I4 and I5 connected at top and bottom by horizontals IS .and II to form squares. There are two squares in each section frame, connected in spaced parallel relation by longitudinal angle bars I8 and I9 at the top and similar angle bars 20, 2|, 22 and 23 at the loottom. Top bars I8 and I9 are so positioned as to act as guides and abutments to positively 'prevent tipping of or side movement of the Aegg trucks during oscillation, while bars 263 to 23, inclusive, are spaced to .form pairs of tracks'on which the trucks are guided. It will be under- `stood that, A-w'henlall 'sectionsare in corresponding rotational-positions, `the corresponding bars kLI`8,'I`9, etc., are in alignment to form, in effect, continuous guides and tracks llongitudinally throughout the housing. Because Aof the fact that tracks 2 do not .permit an-ysubstantial delformation of `frames I3,it.isnotessential that the verticals I4, I and horizontals I6 and I'I be connected with great ,rigidityand I have shown them -asconnected by simple gusset or corner plates Zit-riveted or welded inplace. Indeed some slight deformation'of the rectangular frames I3 may be desirable to accommodate possible irregularities `in the tracks .2.

In the model shown, and referring to Figure l, 'the right upper land lower plates 24 and the left lower plate .24, .are provided vwith bearings, plain Yorf-antifriction,each of which journals a grooved roller 25 each tting overithe angeof a track, -`in vthe same manner as is .indicated at 26, `Figure 2. Thus, for example, 'the upper, right rollers '25 .of each section, may be mounted on a common axle such as a plain cylindrical shaft, journaled in bearings in plates 24; or each plate ymay simply carry an outwardly projecting-stub `shaft on which -the corresponding roller is journaled. Either construction .is satisfactory. Thus, where a commonaxle is used, rollers .25 are lidentical in size and vshape with rollers .32 shown at Figure.2. The only difference is that rollers 25 have a round central hole snugly tting their axle shafts, .instead of the'square central hole of rollers 32.

The upper left rollers are somewhat different in construction and mounting. At this corner as shown at yFigure 2 `each plate 24, 24 has an aperture within which its the outer race 121 of an antifriction bearing 28, whose inner race -29 has a .square opening to receive la. correspondingly square shaft 3G. The -bearing may be retained in place by retaining rings 3L Figure'Z, shows the rear end of the shaft 3i! of the first section, `for example, and the forward end of-shaft 3B of the second section. The roller 32 is a duplicate of .the rollers `2li except that it'has a square central opening to fit the shaft 30. vShaft .33 is 'journaled in the same manner as Vby bearing 28', as .shaft .30 an-d the Ysame reference .characters, primed, have been used to designate corresponding .parts vHence detailed description is unnecessary. However, roller :33, in addition to anges,.has gear teeth on its .central portion, in mesh with teeth II of its r:track so that, as the shaft is rotated, the section is positively rotated on its Vtracks .2.

The yendof shaftJ projects L ri'lrst .incubator section.

-a projection on nut 152.

beyond roller 32 about two-thirds of the distance separating 32 and 33, and carries a sleeve 34 having a squared center opening 35 with a smooth lit. This sleeve has a plunger 36 extending through a radial hole in the sleeve to engage either of two notches 3'I in the end of shaft 30. A leaf spring 38 is attached at one end to sleeve 34 and has its other end bearing on plunger 36 to urge the same into one or the other of the notches to thus yieldingly'hold the sleeve in a first position where it is "free of the adjacent .end of shaft 3G or in a second position where it 'engages over the end of 30. Thus, by sliding -th'e sleeve, the two shafts 3!) and 30' may be coupled or uncoupled as desired and the sleeve "is positively held in selected position.

It will be understood that each incubator section has a squared shaft and that each shaft 3U, 3U etc., is journaled at both ends, with a roller 32 at its rear end and a roller 33 at its viorward ;end. Elms, when.y .all .sleeves 'are .s'lid to the right .as viewed.in I.Eigure `2, allfsquared shafts. are connected for rotation unison and all incubator sections are oscillatedin synchronism. Furthermore, .by sliding .any sleeve it'o '.theflet, allsections to the left may beoscillated, 'while those .to :thefrightrernain atrest. .Inthis way, anyselected number .of .sections may be oscillated without rmoving the .remaining-:sections.

.Power means :are ',provide'dfor oscillating the sections. This zmeans, in :the :model shown, .is va A.reversible motor .39 bolted Yto .a base40 which, -in;turn, is :bolted to the verticalsM, I4', of .the The :base may .be .of .metal orY heavy plywood as `:shown at Figure Y3, .also Ycarries the speed rreducer :and .control auxiliaries for the motor. sh'ownas a conventional worm andgear device -4I bolted .to the base '40 `and having an input shaft to which is rixed a relatively large .pulley 42.driven Vfrom asmaller Apulley l44 .on .the .shaft of motor 39, by a V-belti43. :The .outputzshaft -45 .of speed reducer lII has Aa sprocket 46 fixed .:on=.one projecting end thereof. A chain .fill extends about thissprocketan'd Aa .sprocket .48 'ol'` about equal size, ixed'fto the '.squared :forwardly -ypro'jectingend of the squared .shaft 3B .of .the

lrstdncubator section. Thus, as motor :rotates in :one -direction .'or vthe rother .the rst isection and any 'subsequent sections .connected therewith by sleeves 34, are oscillated Aat .greatly re- -duced speed, .about .axis r3.

Control means :are provided .Lto `periodically energize `the motor to oscillate the sections through a predetermined :angle, about .45", .iirst in one direction and then .in the other, asis necessary for fthe :hatching of the eggs. .This

.fmeans includes 1a threaded .shaft 48 directly coupled by .flanges 59 with the left .projecting .endof shaft `@Sas .viewed in'FigureS. Theshaft is journaled in bearings Ell and .5I iboltedto base=4 and .carries .a nut '.52 held .against rotation kby .any suitable means .not fshown, :such as a rod .mounted 'below shaft .148' .with its ends fixed in the base of bearings 53, 5I and :passing .with :a .smoothit tthrough the .lower portion of the nut :A .pair of bell .cranks 53 and 54 -are .pivoted fon ibase 245, as .shownand have .downwardly projecting arms 53a and 54a, each provided with a .contactscrew havingkits end in the path of The horizontal arms 53h and 54h have electrically insulated ends each carrying a contact which, when thercranks The .speed .reducer is are in the position shown, engage respectively, fixed contact screws 55 and 56 threaded through an insulating block 51 fixed to base 4D. The cranks are urged into contact closing` position by springs 58 and 59 acting between arms 53a, 54a, and abutments on base 40. A combined reversing and selection switch is mounted on base 4U with its actuating plunger positioned directly beneath and in contact with the ends of both arms 53o and 54h. Thus, as nut 52 reaches the left end of its travel, crank 53 is pivoted to separate the contact on arm 5312 from contact 55 and, substantially simultaneously, to depress the plunger of switch 15, reverse the circuit through motor 39 and transfer control of the motor to the other bell crank and contact. When nut 52 reaches the right limit of its travel, it engages and pivots crank 54 to thereby separate its arm 54h from contact screw 56 and, substantially simultaneously actuate the plunger of switch 15.

An electrically controlled contact closing clockwork 60, is conveniently mounted on base 40, together with a relay 6I and a junction box 62. Conventional cable leads, which may be armored, lead from the junction box to the motor, clock, contacts and relay. A flexible cable 63 extends from junction box 62 to a lead in and master switch box 64 and supply cable 65.

The circuit is shown at Figure 4 where it will be noted that clockwork 69 includes a contact arm 64' rotated to periodically close the circuit by contact at 65. This period is approximately two hours, but it is contemplated that a known type of clockwork may be used wherein means are provided for varying the rotational period as desired. Alternatively a mechanical springdriven clock may be used if desired.

As previously intimated, switch 15 comprises two sections, rst, a reversing switch 15a and a selection switch 15b'. The switch is a well known ratchet-type instrument wherein when its plunger is actuated once, it reverses the contacts in section 15a while simultaneously rotating through 90, an arm 15e in section 15b. In2

Figure 4 the operating connection between the two sections is indicated by dotted line 15d. The connections and proportions are such that when nut 52 reaches the left end of its travel,

the frames I3 then connected by sleeves 34, are= in their limiting position of counter-clockwise rotation. Conversely, when the nut reaches its right limit of travel, said incubator sections are in their limiting position of clockwise rotation.

Assuming that the incubator is loaded and thef desired number of sections are connected by sleeves 34, the switch is closed to supply current and start clock 60. Motor 39 remains at rest since the relay contacts controlling the same,

are open. Arm 64 now rotates and at the end of switch section 15b, lead 1D, arm 54h, contact 56,*

lead 1I, the remaining two contacts of reversing switch section 15a. connected at that time and lead 12 to the other side 13v of the supply line. Relay coil 6Ia is then energized to establish a holding circuit from line 66, lead 14, relay bar 6 Ib,"

through coil 6 Ia and the circuit previously traced.

Motor 39 now rotates and pivots the incubator sections clockwise. Simultaneously nut 52 is translated to the right. When the incubator sections have reached the desired limit of clock-7 wise rotation, nut 52 engages and pivots crank 54 to thereby separate arm 54D from contact 56 and break the circuit, whereupon relay 6I opens as coil 6Ia is de-energized. At substantially the same instant arm 54h actuates switch 15 to reverse the contact connections in section 15a, and pivot arm 15e through 90, to thereby transfer circuit control to arm 53h and contact 55. Arm 64 having moved off its contact 65, the incubator sections remain in limiting position of clockwise rotation until the arm again engages contact 65 to close the circuit and establish a holding circuit through relay 6I, as previously described. Because of the new position of switch sections 15a and 15b, current now flows from line 66, lead 14, relay arm 6Ib, solenoid 6Ia, lead 61, switch section 15a, lead 1I, contact 55, arm 53h, lead 14, arm 15e of selector switch 15b, lead 69, motor 39, lead 68, the remaining two contacts of reversing switch 15a, and lead 12 to the other side 13 of the supply. A holding circuit is established as before and motor 39 now rotates in the reverse direction to move the incubator sections counterclockwise 45 to the other limiting position. The incubator sections connected for oscillation are thus'moved at selected intervals in a manner which will hatch the maximum number of eggs.

At times, as when eggs are to be loaded, or chicks removed, it is necessary to rotate the sections to central position wherein all track sections 20, 2l, 22 and 23, are in alignment. For this purpose a manual control is provided by making relay 6| a double throw instrument so that its bar 6I b is spring-pressed upwardly, except when solenoid 6Ia is energized, to close a circuit which may be traced from line 66, lead 16, a reversing switch 11, leads 18 and 69, motor 39, lead 19, switch 11, circuit switch 3U, lead 8|, relay bar 6Ib and lead 12 to the other side 13 of the line. Thus at any time except when solenoid 6 Ia is energized, switch 11 may be thrown for the desired direction of rotation of motor 39, and switch closed to cause the motor to rotate until the track sections are in central, aligned position. Since the speed reducer 4I has a high reduction ratio, it is irreversible and acts to hold the sections positively in whatever position they have at the time motor 39 is de-energized.

The general external appearance of a sevensection machine, is indicated at Figure Ffwhere the entrance and exit tracks may besupported at floor level, by framework generally indicated at 82 and 83. The ends of the housing I are provided withpairs of doors 84 and 85 whereby the housing may be closed. In Figure 5 an egg truck or rack 86 is moved part way into the incubator.

Referring to Figure 1, it will be noted that each truck comprises a simple frame built up of angle sections and provided with bearings 81, axles 88, and anged wheels 89 by which the truck may be easily moved along the tracks. The trucks are provided with superposed angles 89', 9U, etc.

(Fig. 6) secured to each corner upright as by welding whereby trays 9I may be slid into the truck from the ends to load the same. Means are provided at the sides of each truck to prevent the trays from sliding out of the truck when the frames are oscillated.

The trucks, when loaded into the incubator are spaced to provide a central passageway. Flooring sections 92 are secured to the lower horizontals I1 to provide a walk along which an operator may pass to inspect the eggs or to move trucks from one section to another. At the top of each section, a fan 93 is mounted on a plywood base 94 .the art.

escasos :secured: across Vand'acentrall-yl oi .'thetophorizon- .talsflli iofzthesection. :The :fans maybe supplied ibyfcables, :not shown, `from a. lead :95, F-iguret. The 1'cables' between ianschave'sa llength .suicient ytoY enable all if ans .to :be driven while oneror ancre sections aremot bei-ng'oscillated. .OrLdsconnectablepcouplingsfmay be .providedrso thatthe fans :ofthesections notlneingoscillated,.aremct driven.

Heating -mea-ns .are provided, V.Lmnventionally :shownfas steam orhotwatercoilsuril support- ;ed fand :maintained 'in .relation-Joy 'iairleads 19.8 Isupported fromfhorizontalsfl zby brackets' and ntill). .The noils of ieachisection.arerseparaterom those of the rotherxsections" and .are connected zby ,flexible .hose couplings'suchfas :i101 with .supply and 4exhaust Vheaders 11.92 v.and .1113. Valves '141313, M5 Abetween the headersand .each #flexible hose .coupling are provided to. enable heat to any coil ,section ito tbe turned ofi.' .Alternatively electric heating coils zmay beiemployed. .At thebottom,

..waterevaporating pans 51206, :mi lare provided supplied from :headers clizia v and rli, contrclledxby -valves :l IB, 'il l, respectively at the fronteof rthe L-machine. VSeeliigure .Ventilatinglouvressuch 4:as l'l-2.Figur.e 5,'areprovided at each end. Yllhe effective vopening of ,these may be varied v-by .any suitable mechanism, under control-tof aknolb lit-3. Headers :iZaand 1:93 .are adapted, by means-,not

rshown, :for selective connection :either with 'a source .of :hot water,;or Ywith a source for cooling liquid, whereby the temperature within the in- "cubatormay .be fully controlled at fallftimes.l

In operation where .continuous production :of

'chicks Iis desired, as :at rthree-day intervais and Where a seven-.section vincubator vis used, first vand second trucks. areloaded Aandxmoved finto the iirst section. 1Ihe sleeve `Sli between `this and `.tlfie second section is moved to :uncoupled position,

fand the .master switch closed. .At the send of lthree days, vthird and 'fourth'trucks are Aloaded, therstand secondsections are coupled oyfslepeve 34, the rstftwo trucks are 'Jnoved into the v:secfond section .and v.the third .and .fourth trucks :are `moved yintothe rst section. .This Y:procedure is repeated :at vthree-.day .intervals .runt-il .the sentire seven sections lare loaded. However, 'when this lprocedure is '-followed, inaccordance with :well known procedure, A.the .seventh .section .remains uuncoupledso that 1theeggs lare 'quietxfor thelast "three days Vvbefore hatching. vgat-theendoiLtvi/ enty-one 4days vlthe eggs in #the first and `.second truckshave hatched land these trucks #are moved out through `doors 35.- T-Ihus, continuous .production fis ypossible with a batch Aoi- `.chicks .ibeing Vhatched at vrinter-vals dependent upon 'the :number 'oi 'incubator sect-ions employed and the `number of `trucks loaded into the machinel ataeachinfterval. lf desired one truck "may fbe 'loaded v.in-to the machine zatone and one-half .day intervals instead of two at three-dayslintervals.

Alternatively, `all sections may be loaded-iat vthe same time, coupled for v`'oscillation lby sleeves 3i-and rocked for eighteen dayswhen the power A-to motor til is turnedofi.v

`I have thus .provided a large-capacity'incu- Abator which, While relatively simple andin'expensive to produce, is :highly YAeliic'ient:and flexible in operation. Becausellthe-:eggtrucksmayzbe loaded and then run rdirectly into ytheu nac'lfiinethe vexpense or" transferring egg trays rombne :part -of the -incubatorito .anothersat the .end .of .eighteen days, is eliminated. Numerous iotherzways of ns- .ing Athe incubator, will occur `to those :skilled :in @thertypes of @poul-try eggs Vmay ,be hatched .in the machine -with equal V.ediciency f-tion and-,thenvin areversefdirection.

Because it. is amnecessary'to handle-fthefzggs, the even temperature at Iwhch they jare maintained and the smooth operation ofthe 4machine, zazmaximum percentage of Yhatched feggs is assured. Furthermore, incubator sections may beradded at relatively low costas the; production requirements ofthe .owner increase.

The-fan -93 may be inverted Yfrom the position :shown :so 'that the -motor thereof is labove the blades. Any suitable bracket vmay -be used for ,supporting the fan insuchan inverted posi-tion, either -on vor .underneath supported.

While truck-S86 areshownatFig. -1 as comprising Aa single stack of traysit-will be understood that this is .merely one example, and that each truck may support :two stacks of trays in sideby-side relation. 4In suchaa construction the two stacks would be spaced laterally, in a viewcorrespondingto Fig. il, and .afpartition would extend -cent-rally vand vertically betweenthe two stacks. The trays are of standard construction-=with walls Von all four sides to vprevent thezeg-gs .and chicks `:from falling out.

While I have shown a,preferred..form of the invention as now known .to me, numerous. modiiications and substitutions will occur to `those skilled in the art, `after a .study of the present disclosure. A .number of `these have been .suggestedherein. For this reason, .the disclosure is .to be taken in an illustrative rather than a limiting sense. With-inthe .scope of the subjected claims, fall modifications, and substitutions of equivalents, are reserved.

Having now fully disclosed my invention, what I claim and desire to secure ley-Letters Patent is:

1. .In .an incubator, ahousingqa frame in said housing, a plurality of Aaligned sections, means mounting said sections in contiguous aligned yrelation `on said frame iior rocking about a Ycom- ,mon axis, means .operable to rock all or selected .ones only of said sections about .said -axis from a `single source vof power, and track means carried within eachsection vand forming a continuous track through said incubator when said sections are .in predetermined rotational relation about said. axis, said .track means 4being adapted 'to support .egg trucks within each said section.

2. Inan incubator,v circular track means having an opencenter., an Yopen frame, rectangular in cross section mounted on and within said track means for rocking movement about the central axis of said track means, .gearing between said track means .and frame, means carried by said .frame to Ysupport an egg truck therewithin and v,for `movement along ,saidaxis and vfor rocking therewith, .and power :means connected to drive said gearing .to .rock said frame.

3. 4An .incubator comprising arame including a -pair of circular tracks spaced along and concentric of a common axis, .said frame carrying a carried within saidl frame .andextending parallel to :and Valong said axis for. guiding .and .supporting van egg truck for .movement therea-long, power means connected to drive said gea-r means, and

means-.adapted to control said power vmeans to .rock saidrframe fon said tracks rst .in-one direc- 4. An incubator as recited in claim 3, said power-means comprising an electric motor, a circuitftherefor, saidhcontrolmeanscomprising time mechanism periodically `closing ,said .circuit to operate said motor, and means responsive to the rotational position of said frame for opening said circuit.

5. In an incubator, a pair of circular tracks each comprising a channel member with inwardlyLdirected anges, means mounting said tracks in xed parallel spaced relation concentric of a common axis, said channel member having an arcuate rack fixed thereon concentric of said axis, a rectangular frame substantially fitting within said tracks, rollers on said frame journaling the same on said tracks for oscillation about said axis, one said roller including a gear in mesh with said rack, whereby rotation of said one roller effects pivotal movement of said frame, and track means carried within said frame in parallel relation with said axis for guiding an egg truck therealong.

6. An incubator as in claim 5, reversible power means, a driving connection between said power 20 means and said gear, and means effecting periodical reversal of said power means to rotate said frame through a predetermined angle.

LOT J. SEAC'AT.

10 REFERENCES CITED The following references are of record in the le of this patent:

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